/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.dx.rop.annotation;

import com.android.dx.rop.cst.Constant;
import com.android.dx.rop.cst.CstString;

/**
 * A (name, value) pair. These are used as the contents of an annotation.
 */
public final class NameValuePair implements Comparable<NameValuePair> {

	/** {@code non-null;} the name */
	private final CstString name;

	/** {@code non-null;} the value */
	private final Constant value;

	/**
	 * Construct an instance.
	 * 
	 * @param name
	 *            {@code non-null;} the name
	 * @param value
	 *            {@code non-null;} the value
	 */
	public NameValuePair(CstString name, Constant value) {
		if (name == null) {
			throw new NullPointerException("name == null");
		}

		if (value == null) {
			throw new NullPointerException("value == null");
		}

		this.name = name;
		this.value = value;
	}

	/** {@inheritDoc} */
	public String toString() {
		return name.toHuman() + ":" + value;
	}

	/** {@inheritDoc} */
	public int hashCode() {
		return name.hashCode() * 31 + value.hashCode();
	}

	/** {@inheritDoc} */
	public boolean equals(Object other) {
		if (!(other instanceof NameValuePair)) {
			return false;
		}

		NameValuePair otherPair = (NameValuePair) other;

		return name.equals(otherPair.name) && value.equals(otherPair.value);
	}

	/**
	 * {@inheritDoc}
	 * <p>
	 * Instances of this class compare in name-major and value-minor order.
	 * </p>
	 */
	public int compareTo(NameValuePair other) {
		int result = name.compareTo(other.name);

		if (result != 0) {
			return result;
		}

		return value.compareTo(other.value);
	}

	/**
	 * Gets the name.
	 * 
	 * @return {@code non-null;} the name
	 */
	public CstString getName() {
		return name;
	}

	/**
	 * Gets the value.
	 * 
	 * @return {@code non-null;} the value
	 */
	public Constant getValue() {
		return value;
	}
}
